In general, an outdoor advertisement device is installed in a building rooftop or other structures to display advertisement requested by an advertiser. Because such an outdoor advertisement device can display advertisement contents through a large-sized advertising board or a large-sized screen, the outdoor advertisement device has high visual transfer effect and is thus much used as one of advertisement methods. Nowadays, at a location in which many persons gather such as the bus stop side and a shopping center, an outdoor advertisement display device using a light emitting diode (LED) display is installed and operated.
When a natural disaster such as heavy rain, typhoon, and cold wave occurs, in order to notify or warn the natural disaster, a disaster prevention text is displayed through a large-sized advertising board or a large-sized screen installed at outdoor.